Roasting or drying furnace



Patented lune 20, |899.

(Application Bled July 25, 1898.)

2 Sheets-Sheet l.

(No Model.)

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Patented :une 20,1899.

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(Application med July 25, 189B.)

2 Sheets-Sheet 2 (No Model.)

Gbbowm WILLIAM HARVEY, OF DENVER, COLORADO,

ROASTING OR DRYING FURNACE..

rSP1-LCIFICATION forming part of Letters Application led July 25,1898.-

To all whom, it mrtg/cancelen Be it known that I,` WILLIAM HARVEY, acitizen of the United States of America, residing at Denver, in thecounty of Arapahoe and State of Colorado, have invented certain new anduseful Improvementsin Roasting or Drying Furnaces; and I do declare thefollowing to be a full, clear, and exact description of the invention,such as will enable others skilled in the art to which it appertains tomake and use the same, reference being had to the accompanying drawings,and to the letters and figures of reference marked thereon, which form apart of this specification.

My invention relates to improvements in roasting-furnaces, my objectbeing to provide an apparatus of this class which shall be simple inconstruction, economical in cost,

reliable, durable, and efficient in use; and to these ends the inventionconsists of the features, arrangements, and combinations hereinafterdescribed and claimed, all of which will be fully understood byreference to the accompanying drawings, in which is illustrated anembodiment thereof.

In the drawings, Figure l is a vertical longitudinal section takenthrough my improved furnace on the line y y, Fig. 3. Fig. 2 is afragmentary section illustrating the two lower conveyers. Fig. 3 is endeleva-tion of the f urnace. Fig. 4 is a cross-section taken through thesame on the line a: Fig. 1.

Similar reference characters indicating corresponding parts in theviews, let the numeral designate the outer wall ot' the furnace and 6the fire-clay lining surrounding the combustion-chamber 7, in which islocated the firegrate 8. Located above the fire-grate and journaled insuitable boxes in the end walls of the furnace are a number of revolubleconveyers 10, 12, and 13. Each of these conveyers is composed of anouter tube A, an inner tube B, and a spiral plate or screw-threadlocated between the two tubes and connecting them with each other. Theinner tubes B project beyond the outer tubes, and their rear orleft-hand extremities (referring to Fig. 1) are provided withgear-wheels 14, 15, and 16, respectively, through which the tubes pass.The gear 16 meshes with a smaller gear 17, fast on a shaft 18, carryinga pulley 19, (shown in Patent No. 627,333, dated June 20, 1899.

stanno. 686,785. (rameau.) y

dotted lines,) which may be connected with any suitable motor foroperating the conveyers. As the gear 17 is turned in the directionindicated by the arrow, (see Fig. 3,) the gears are rotated in thedirection indicated by the adjacent arrows in the same figure.

A conduit 20, communicating with the chamber 7, leads to one extremityof the inner tube B of the uppermost conveyer. The smoke and4 productsof combustion, as well as the fumes from the ore, pass from the chamber7 by way of this tube to a conduit 21, leading to a suitable stack. (Notshown.)

In using the apparatus the ore or other material to be treated is fedinte the forward eX- tremity of the tube A,belonging to theuppermostconveyer 13, by way of a chute 23. The rotation of thisconveyer carries the material rearward between the two tubesA and Bthrough the medium of the interposed screw-thread O. After reaching therear extremity of the conveyer 13 the material is discharged from theconveyer by Way of a chute 132L into the tube A of the conveyer 12 andcarried thence in the opposite direction or forwardly through thelast-named conveyer, since this conveyer rotates in a direction oppositethe conveyer 13. After reaching the forward extremity of the conveyer 12the material is discharged by way of a chute 12 into the tube A of theconveyer 10, through which it is again carried rearwardly and dischargedfrom the apparatus. While traveling slowly through the conveyers theprocess of roasting is going on through the agency of the heat generatedin the combustion-chamber 7, the

outer tubes A being directly acted upon by the heat.

The tubes B of the conveyers 12 and 13 are perforated their entirelength, while the corresponding tube of the conveyer 10 is perforatedonly a portion of its length. (See Fig. 2.) The forward extremity of thetube B of the conveyer 12 is provided with an interior lefthand screw Hfor the introduction of salt, which passes through the perforations inthe tube, coming in contactwith the ore between the tubes A and B. Thissalt meets the'ore,

which is traveling in the opposite direction, and is discharged with itinto the lowermost conveyer 10, whereit meets the steam gen- IOO veratedby the introduction of jet of water A la chute 24 and thewater by way ofa pipe 25. (See Fig. l.) Of course the conveyers may be supplied withany other substances which may be found desirable or necessary incarrying out'the roasting process, whose function is the removal fromthe ore of the refractoryelements,asheretoforestated. The course of theore while traveling through the conveyers isindicated by the arrows inFig. 1.

It must be understood that any number of revoluble conveyers may beemployed in the construction of my improved furnace or drier withoutdeparting from thespirit of the invention.

It may be stated that one reason for having the tubes B of the conveyorsopen-ended is to permit the attachment of hoods or other apparatus forthe purpose of condensing or saving any mineral values that may haveescaped with the fumes. The hood apparatus is not shown, inasmuch asnothing is claimed thereon in this specification.

Having thus described my invention, what I claim isi l. In aroasting-furnace, the combination with the combustion-chamber andanurnber of conveyers journaled therein, means for delivering thematerial to'one of the conveyers,

means for discharging the material from one conveyer to the other, meansfor rotating the conveyers, whereby the material is made to L travelthrough the adjacent conveyers in opposte directions, and a conduitcommunicatf in gwith the combustion-chamber and leading y to one end ofthe uppermost convcyer, whose opposite extremity communicates with lthesmoke-stack.

2. In a roasting-furnace, the combination with the combustion-chamber,of a number of conveyers journaled therein, each comprising twoopen-ended tubes, one placed within v the other and connected by aninterposed screw-thread, means for delivering the mate- 4rial to one ofthe conveyers, means for discharging the material from one conveyer tothe other, means for rotating the conveyers, whereby the material ismade to travel through the adjacent conveyers in opposite directions,and a conduit communicating With the combustion-chamber and leading' toone .end of the inner tube of the uppermost conveyer, the oppositeextremity of the last- .named conveyer communicating with theEsmoke-stack.

3. In a roasting-furnace, the combination with the combustion-chamber,of a number of conveyers journaled therein, each compris- "ing twoopen-ended tubes, one placed within lthe other and connected by aninterposed iscrew-thread, the inner tubes being perforated, means forconveying the material to one of the conveyers, means for rotating theconl veyers, whereby the material is made to travel through the adjacentconveyers in opposite directions, and a conduit communicating with {thecombustion-chamber and leading to the ,inner tube of the uppermostconveyer whose opposite extremity communicates with the smoke-stack. I

In testimony whereof I affix my signature fin presence of twowitnesses.,

WILLIAM HARVEY.

Vitn esses A. J. OBRIEN, EDITH HIMSWORTH.

